An important series of 4-pyridone herbicides is disclosed in U.S. patent application No. 591,661, filed July 3, 1975, and in Belgian Pat. No. 832,702. These compounds, which have a phenyl or substituted-phenyl group at the 3-position, are exceptionally potent herbicides particularly for use in cotton cropland.
The present invention belongs to the field of synthetic organic chemistry and agricultural chemistry and provides an economical and convenient process for the preparation of intermediates used in a synthesis of the 4-pyridone herbicides.